This invention relates to automatic dispensing caps, and more particularly to dispensing caps employing two-way valves which allow product to flow out and air to flow in.
Heretofor, bottles for dispensing a wide range of items including household cleaners, foods and like products typically employed a cap which required removal each time the product was to be dispensed; and then, after dispensing, it was necessary to replace the cap to prevent spilling or evaporation.
Bottles and caps of this type are cumbersome, as when the cap is removed, the bottle is open and susceptible to spillage. This is especially true in the case of soap products, such as shampoo, where there is also the problem of water or other materials entering the opened bottle, thereby contaminating the product.
In addition to contamination and spillage, an open bottle is susceptible to becoming clogged around its neck from the remains of the product that adheres to the rim of the neck and dries out.
Further, when storing or shipping bottles having these conventional type closures, changes in the external pressure of the surrounding atmosphere will cause the bottles to deflect inwardly, making the bottle appear old and worn. Manufacturers, in attempting to overcome this atmospheric pressure problem, had to resort to using stronger, thicker bottles at greater costs.
Many attempts have been made to eliminate the problem of separate bottle and cap closures by constructing a cap which is permanently attached to the bottle and opens and closes automatically without the need of a separate closure.
Examples of such prior attempts are disclosed in U.S. Pat. No. 4,226,342, issued Oct. 7, 1980 and in U.S. Pat. No. 4,230,240, issued Oct. 28, 1980, both to Laauwe, which include dispensing caps for use on a squeeze bottle, wherein internal pressure causes a diaphragm forming the top of the cap to move up off of a seat comprising the upper opening, thereby dispensing the product. These and similar attempted modifications employ a stationary seat and a deflatable diaphragm or top. Such devices do not completely solve the problems of the prior-art, as they are subject to leakage even in the closed position, and do not eliminate the problem of clogging at the dispenser's opening.
In addition, these prior modifications do not adequately provide any means for recovery of the bottle shape after squeezing;--nor do they provide any adequate means to prevent premature dispensing of product from the bottle during shipping, except for the conventional shipping seal.